Device for retarding the speed of lowering of self-run-down lifting-jacks



F. L. GORMLEY.

DEVICE FOR RETARDING THE SPEED OF LOWERING OF SELF RUN DOWN LIFTING JACKS.

APPLICATION FILED JULY 26, I920.

Patented J 11116 28, 19-21.

2 SHEETS-SHEET 1.

Lwenior: .FrwzkZ.GormZe by V ,F. L. GORMLE Y. DEVICE FOR RETARDING THE SPEED OF LDWERING 0F SELFRUN DOWN L IFTING JACKS-v 4 v APPFlCATl-ON mcn' JULY 26; 1920. 1,383,202.

Patented Ju ne 28,1921.

2 SHEETS-SHEET Z- UNITED STATES PATENT OFFICE.

FRANK L. GOBMLEY, OF BROOKLIIN'E, MASSACHUSETTS.

DEVICE FOR RETARIDING THE SPEED 01 LOWERING OF SELF-RUN-DOWN LIFTI'NG- JACKS.

Application filed July 26,

T 0 all whom it may concern:

Be it known that I, F RANK L. GORMLEY, a citizen of the United States of America, and a resident of Brookline, in the county of Norfolk and Commonwealth of Massachusetts, have invented certain new and useful Improvements in Devices for Retarding the bpeed of Lowering of Self-RunDown Lifting-Ja'cks of which the following is a specification.

This invention relates to devices for re tarding the speed of lowering of self-rundown. lifting jacks and has for its object the provision of a single and effective means which'will retard the downward movement of the movable member and prevent its movement at an excessive speed. The invention consists of a bladed member secured to the worm shaft of a liftin jack which is adapted to rotate in one direction only in a casing partially filled with balls or some similar movable material, said material being lifted by said blades a limited distance and then permitted to return to its normal posit-ion in the bottom of the casing.

The invention further consists in certain novelfeatures of construction and arrangement of parts Which will be understood readily by reference to the description of the drawings and to the claims to be hereinafter given.

For the purpose of illustrating the invention, one preferred form thereof is illustrated in the drawings. this form having been found to give satisfactory and reliable results although it is to be understood that the various instrumentalities of which the invention consists can be variously arranged and organized and the invention is not limited to the precise arrangement and organization of these instrumentalities as herein shown and described except as required by the scope of the appended claims.

(if the drawings:

Figure 1 represents a cover plate containing the operating mechanism of a highspeed lifting jack adapted to be lowered under the weight of the load.

Fig. 2 represents a horizontal section of same on line 2, 2, on Fig. 1.

Fig. 3 represents a vertical section on line 3, 8, on Fig. 2.

Fig. 4 represents a diagrammaticv1ew Specification of Letters Patent.

Patented June 28, 1921.

1920. Serial No. 398,913.

showing in dotted line the path taken by the movable material in the casing of the retarding device.

Fig. 5 represents an elevation, partly in section, of the manually controlled braking mechanism, and

Fig. 6 represents an elevation of the actuator for removing the brake arms from contact with the brake wheel.

Similar characters indicate like parts throughout the several figures of the drawmgs.

In the drawings. 10 is a cover plate adapted to be secured to a lifting jack such as is disclosed in U. S. Letters-Patent No. 1,324,345 issued to me Dec. 9, 1919 to which reference may be made for the general construction of the jack.

Through the plate 10 extends an operating shaft 11 for raising the jack in the manner fully described in the above-entitled patent.

The shaft 11 has secured thereto a ratchet 12 which revolves therewith and said shaft also has loosely mounted thereon a gear 13 carrying spring-pressed pawls 14 which are adapted to be engaged by the teeth of ratchet 12 when the shaft 10 is rotated in a reverse direction during the load lowering operation.

This gear 13 meshes with a pinion 16 on a shaft 17 having mounted thereon and revoluble therewith a worm gear 18 meshing with a worm 19 on a shaft 20 freely revoluble in bearings 21 in brackets 22 secured to the inner face of the cover. plate 10.

The shaft 21 has a reduced threaded end 23 on which is mounted a brake wheel 24.

Pivoted at 33 to the bracket 22, secured. to the inner face of the cover plate 10, are two brake arms 34, said brake arms being curved to fit the periphery of said brake wheel 24 and having parallel extensions 35 at their free ends.

Each of the extensions 35 has a socket 36 in its outer face'in which rests one end of a spring 37 the opposite end of which rests in a socket 38 in the cover plate 10 of a bracket 39 secured thereto.

This spring 37 normally retains said brake arms 34: in such frictional contact with the brake wheel 24.- as to sustain the load upon the jack and prevents the jack from lowering under the weight of said load.

Between the extensions 35 of brake arms vented from being displaced by the headed screw 42.

The springs 37 normally retain the brake arms 34 in contact with the periphery of the wheel 24 and prevent its rotation until the actuating lever 41 is moved to cause said flat sided projection to separate said brake arms 34 and remove them from contactwith the wheel 24.

n is self-evidentthat the pitch of the,

worm 19 must be such that rotary movement may be imparted thereto by the rotation of the worm gear 18 which rotary movement is in turn imparted to the brake wheel 24.

r The worm shaft 20 is also provided with a reduced threaded end to which is secured a hub 51 having a plurality of radial blades 52,, 53 extending therefrom.

These blades 52, 53 may be formed integral with the hub 51 or secured thereto in 1 any well-known manner. 7

The blades 52 are inclined in one direction and the blades 53 are inclined in the oppo site direction as indicated in Fig. 4.

These blades 52, 53revolve with the worm shaft 20 within the ring 54 set into the cylindrical chamber 55, said chamber being formed with the bracket 22.

The outer end of the chamber 55 is closed by a plate 56. I

' The blades 52 extend from the inner end of the chamber 55 to a point removed from g the closing plate 56 leaving a passage between its edge and said closing plate through which movable material may pass during the rotation of said blades 52, 53, within said chamber 55.

In like manner the blades'53 extend from said cover plate 56 to a point removed from the inner end of said chamber55 leaving a similar. passage through which the movable material may pass. 7 Y

The movable material shown in the drawings is a plurality of small balls or shot 57 which normally rest in the bottom of the chamber55 asindicated in Fig. 30f the drawings but any other suitable material may be used if desired.

During the lifting operation the worm is not rotated and the blades 52, 53 are at rest.- .Whenthe load has been lifted'the brake arms 34 coacting with wheel 24 will retain the load in its elevated position.

When itis desired to lowerthe load, the actuator lever is moved from the position shown in Fig. 6 and the turning of the cam member 40 will remove the brake members the actuating lever 41 on the 34 from contact with the wheel'24 thereby permitting the jack to lower under the weight of the load.

As soon as the load commences to lower, the worm shaft 20 will be revolved causing the blades 52, 53 torotate through the mass of balls, shot or other movable material in the chamber 55. p

These blades 52, 53'move inthe direction of the arrows at on Figs. 3 and 4 of the drawings and as they move through the movable material 57 said material is forced up the in clined face of the first blade 52 and is lifted thereby until dropped to return to its normal position.

"As the movable material is lifted, it will move outwardly the blade 52 and create a greater leverage thereon and assist in retarding the speed of the worm shaft and prevent too rapid a rotation thereof.

As the movable material 57 moves up the inclined face of the blade 52 and passes over the upper edge thereof, it is forced toward the inner end of the chamber 55 by the blade 53 until the material passes below the lower edge of said blade 52.

This material is then picked up by the second blade 52 and having been droppedtherefrom is engaged by the second blade 53 and the former operation repeated.

It is obvious therefore that in the continuous rotation of the blades 52, 53, the

movable material is picked up by'said blades, travels up the inclined surfaces of the blades- 52 and down the inclined faces of the blades 53 and at the same time said movable material moves outwardly while on said blades 52. 53.

This obstruction of the free rotation of said blades causes the speed of the worm shaft to be retarded sufficiently to prevent its racing or gathering such momentum that it (annot'be stopped readily.

.The balls 57 are of two different sizes as it has been found inpractice that better results are obtained by the use of large and small balls, balls of one size being liable to become wedged and interferewiththe proper operation of the device.

These balls 57 are preferably immersed in graphite to cause them to roll on each other more readily. V 7

When the blades 52. 53 are moved slowly, the balls 57 will-be lifted only a short distance before they are dropped'and return to their normal position but when the shaft 20 is rotating rapidly some of the balls 51 will make a complete cycle, at all times endeavoring to return to their normal position by traveling in a direction opposite to the direc- 1 tion of travel of the blades 52, 53 said balls 57 following the path indicated by the dotted line 60 in Fig. 4. f The amount of retardation may be varied by varying the quantity of balls in the casing, by varying the inclinations of the blades 52, or by varying the lengths of said blades.

This makes a very effective device for retarding the speed of lowering of self-rundown lifting jacks.

I t is believed that the operation and many advantages of the invention will be understood readily without further description.

Having thus described my invention, I claim- 1. In a device of the class described, a revoluble shaft; a member revoluble therewith provided with a plurality of inclined blades; a cylindrical casing for said revoluble member; and movable means in said casing coacting with said blades to retard the speed of said shaft.

2. In a device of the class described, a revoluble shaft; a member revoluble therewith provided with a plurality of blades alternately inclined in opposite directions; a cylindrical casing for said revoluble member; and movable means in said casing coacting with said blades to retard the speed of said shaft.

3. In a device of the class described, a revoluble shaft; a member revoluble therewith provided with a plurality of staggered blades; a cylindrical casing for said revoluble member; and movable means in said casing coacting with said blades to retard the speed of said shaft.

4. In a device of the class described, a revoluble shaft; a member revoluble therewith a cylindrical casing for said revoluble mem her; a plurality of radial blades on said revoluble member alternately removed from the opposite walls of said casing; and movable means in said casing coacting with said blades to retard the speed of said shaft.

5. In a device of the class described, a revoluble shaft; a member revoluble therewith provided with a plurality of blades; a cylindrical casing for said revoluble member; and a plurality of balls in said casing coacting with said blades to retard the speed of said shaft.

6. In a device of the class described, a revoluble shaft; a cylindrical casing surrounding a portion of said shaft; movable material in said casing; and a plurality of staggered radial members on said shaft adapted in their rotation to coact with said movable material to retard the speed of said shaft.

7. In a device of the class described; a revoluble shaft; a cylindrical casing surrounding a portion of said shaft; movable material in said casing; and a plurality of staggered and inclined radial members on said shaft adapted in their rotation to coact with said movable material to retard the speed of said shaft.

8. In a device of the class described, a revoluble shaft; a cylindrical casing surrounding a portion of said shaft; movable material in said casing; and a plurality of staggered radial members alternately inclined in opposite directions on said shaft adapted in their rotation to coact with said movable material to retard the speed of said shaft.

9. In a'device of the class described, a revoluble shaft; a cylindrical casing surrounding a portion of said shaft; a plurality of balls in said casing; and inclined members rotatable with said shaft and movable through the mass of balls, said members being inclined alternately in opposite directions and part of said blades being removed from one end wall of said casing and the others being removed from the other end wall, leaving passages through which said balls are adapted to pass. I

10. In a device of the class described, a revoluble shaft; a cylindrical casing surrounding a portion of said shaft; a plurality of balls in said casing; and means in said casing rotatable with said shaft for lifting said balls and then permitting them to descend.

11. In a device of the class described, a revoluble shaft; a cylindrical casing surrounding a portion of said shaft; a plural ity of balls in said casing; and means within said casing rotatable with said shaft for moving said balls from their normal position and causing them to return in a zig-zag path to their normal position.

12. In a device of the class described, a revoluble shaft; a cylindrical casing surrounding a portion of said shaft; a plurality of balls of different diameter in said casing; and means in said casing rotatable with said shaft for lifting said balls and then permitting them to descend.

13. In a device of the class described, a revoluble shaft; a cylindrical casing surrounding a portion of said shaft; a plurality of balls of different diameter in said casing; and a plurality of inclined radial blades in said casing rotatable with said shaft for lifting said balls and then permittingthem to descend.

14. In a device of the class described, a revoluble shaft; a cylindrical casing sur rounding a portion of saidv shaft; a plurality of radial blades rotatable in said casing with said shaft and yielding obstructions in said casing in the path of said blades.

Signed by me at 746-? Old South Bldg, Boston, Mass, this 23d day of July, 1920.

FRANK L. GORMLEY.

Witnesses:

WALTER E. LOMBARD, NATHAN C. LOMBARD. 

